Question

A claim is ... the closing point of any argument. the starting point for any argument. the supporting details in an argument. the citations available for an argument.

Answer 1

A claim is "The starting point for any argument."

"The closing point of any "argument" is the Conclusion. 

"The supporting details in an argument" is the Main idea.

"The Citations available for an argument" is the Evidence.

Answer 2

It's first you claim, then you come with details. So, it's the starting point for any argument.